EXAM #2: ENDOCRINE PANCREAS ANATOMY Flashcards Preview

Endocrine > EXAM #2: ENDOCRINE PANCREAS ANATOMY > Flashcards

Flashcards in EXAM #2: ENDOCRINE PANCREAS ANATOMY Deck (36):
1

What are pancreatic islets embryologically derived from?

Endoderm

2

What hormone is secreted by Beta cells in the pancreas?

Insulin

3

What hormone is secreted by Alpha cells in the pancreas?

Glucagon

4

What hormone is secreted by Delta cells in the pancreas?

Somatostatin

5

What is contained in an immature secretory vesicle of the beta cells? What happens in this vesicle?

Proinsulin, which is cleaved into Insulin and Protein C

6

How does Clathrin differentiate between an immature vesicle and mature vesicle in the Beta cell?

Immature= clathrin coated
Mature= no clathrin

7

Which has a longer half-life, insulin or protein c?

Protein C

8

Is GLUT-2 dependent or independent of insulin?

Independent

9

What is the mechanism of insulin release from the beta cells?

1) Glucose in via GLUT-2
2) Glycolysis increases ATP
3) ATP binds K+ sensitive channel, inactivating it and leading to membrane depolarized (Sulfonylurea Receptor)
3) Ca++ enters voltage gated channels
4) Insulin is released via exocytosis

10

What drugs target the K+ channel necessary for insulin release?

Sulfonylurea class drugs i.e.
- Gliclazide
- Glimepiride

11

What transporter is necessary for glucose entry in target cells?

GLUT-4

12

Is GLUT-4 dependent or independent of insulin?

Dependent

13

What does insulin do to target cells?

- Causes insertion of GLUT-4 transporters into membrane
- Glucose enters the cell

14

What is the embryologic origin of the adrenal cortex?

Mesoderm

15

What is the embryologic origin of the adrenal medulla?

Neural crest cells

16

What is required for the differentiation of neural crest cells to chromaffin cells in the adrenal medulla?

Cortisol

17

What is the mnemonic to remember the parents vessels of the suprarenal arteries?

IPAR

Inferior phrenic= superior suprarenal a.
Aorta= middle suprarenal a.
Renal= inferior suprarenal a.

18

What is the origin of the cortical and medullary arteries?

Supracapsular arterial plexus (plexus under the capsule from the suprarenal a)

19

What capillaries receives the hormones from the adrenal cortex?

Sinusoidal capillaries in the cortex

20

Where does the right suprarenal vein empty?

IVC

21

Where does the left suprarenal vein empty?

Left renal vein

22

What are the three zones of the adrenal cortex?

GFR:

Glomerulosa
Facsiculata
Reticularis

23

What is the mnemonic to remember the hormones released from the zones of the adrenal cortex?

Salt, sugar, sex

Aldosterone= G
Cortisol= F
Androgens= R

24

Histologically, what do you NOT see in the adrenal cortex would be expected b/c of the glands high output of secretory products?

Secretory vesicles; steroid hormones diffuse across membrane unlike peptide hormones

25

ACTH has a stimulatory effect on which two parts of the adrenal cortex?

Fasiculata and reticularis, NOT Glomerulosa

26

What is the expected gross finding in the setting of ACTH excess i.e. Cushing's?

Cortical hypertrophy contributed by Fasiculata and Reticularis ONLY

27

What hormone has a major inhibitory effect on ACTH and cortisol secretion?

Glucocorticoids

28

What segmental levels of the SNS innervate the adrenal medulla?

T8-L1

29

Catecholamines are derived from what amino acid?

Tyrosine

30

List the steps in catecholamine synthesis?

1) Tyrosine
2) DOPA
3) Dopamine
4) NE
5) Epinephrine

31

What enzyme converts NE to Epi? What hormone activates this enzyme?

Phenylethanolamine-N-methyltransferase, which requires cortisol

32

In catecholamine synthesis, which is the only product that is NOT made in the cytoplasm?

NE

*Dopamine to NE enzymatic step occurs in the secretory vesicle

33

When catecholamine synthesis increases, what binding protein also increases?

Chromogranin

34

What is the Organ of Zuckerkandl?

Ectopic adrenal-medulla tissue in the region of the aortic bifurcation

35

A tumor of the Organ of Zuckerkandl i.e. a pheochromocytoma, is expected to increase the output of what?

Norepinehprine

*Without cortisol from the adrenal cortex, cannot convert NE to Epi

36

In Congenital Adrenal Hyperplasia, with the enzyme that produces cortisol deficient, describe the sequence of events that results in ambiguous genitalia in the female?

1) Decreased cortisol and shunting down the other pathways
2) Adrogens increased
3) Decreased cortisol leads to increased ACTH causing positive feedback and increased androgens

*Leads to ambiguious in the female patient